A D.S.P (TMS320lf2407) based implementation of P.W.M for single-phase acdc bipolar converter with a unity power factor

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1 A D.S.P (TMS3lf47) based implementation of P.W.M fo single-phase acdc bipola convete with a unity powe facto H. DENOUN, N. BENAMROUCHE, S. HADDAD, S. MEZIANI and S. AIT MAMAR Abstact This pape deals with the study and the implementation of a D.S.P (TMS3LF47) contolled single-phase AC/DC convete using PWM stategy, including sinusoidal tiangula stategy (SPWM). Afte the desciption of its functioning pinciples, its modeling and the convete contol system, we have analyzed the modeling paametes influence on the convete behavio using that stategy. The study was led by simulation and validated expeimentally on testing gound with a DSP designed and built in the laboatoy. Keywods Tiangulo-sinusoidal stategy, Insulated Gate Bipola Tansisto I.G.B.T, Digital Signal Pocesso (DSP), Matlab Simulation. S I. INTRODUCTION INGLE-phase convetes ae widely used in industial applications, such as standby powe supplies and uninteuptible supplies. A block diagam epesentation of a s i n g l e -phase convete is given in (figue ). The convete consists of fou switching devices (epesented as ideal switches) connected in the fom of a bidge. The contol scheme is implemented using TMS3LF47 DSP contolle. The powe supply of vaiable speed systems equies the use of AC/DC convetes with diodes o thyistos; howeve, these convetes geneate hamonics in the input netwok causing voltage wave fom distotions, leading to powe facto deteioation of the input netwok [], []. To avoid these distubances, the taditional ectifies ae eplaced by pulse width modulation convetes which ae able to: - impose a sinusoidal cuent wavefom whateve the type of load; - contol the netwok powe-facto; - ensue the functional evesibility of the installation without esot to an auxiliay bidge in the contay to the taditional convetes [3], [4], [5], [6], [7], [8]. In this wok, we pesent a study of a single-phase ectifie contolled by PWM stategy, allowing the fulfillment of all these equiements. We look at its constitution, its pinciple of opeation and its modelling, then we show the theoetical esults obtained by a digital simulation by applying contol technique of pulse width modulation namely the tiangulosinusoidal stategy. The pactical ealization of this convete enabled us to cay out tests at the laboatoy. The esults of the pactical tests obtained will be compaed with those obtained by simulation. Fig. single phase AC/DC Convete II. MODELLING OF THE STUDIED SYSTEM Fig. shows the schematic diagam of the studied system and indicates the adopted notations. The convete is made of fou switches K i (i=,4) odeed bidiectional while unning. Each one contains I.G.B.T tansisto T i and one diode D i placed in antipaallel with the tansisto. The convete is connected at the output of the input tansfome. L indicates the total inductance of the netwok and of the leakage inductance of tansfome efeed to the seconday. Unde these conditions, v is the pesumably sinusoidal voltage efeed to the seconday which is constant. A capacity C is placed at output of the convete which is fed by a cuent souce because of inductance L, Issue 4, Volume 5, 354

vˆ δ δ î ϕ û e jl ω î û e jl ω î vˆ Fig. vecto diagam The system opeation can be descibed by the vecto diagam shown in Fig. whee i and u e ae the ms value of the fundamental hamonic Fouie expession.

2 vˆ δ δ î ϕ û e jl ω î û e jl ω î vˆ Fig. vecto diagam The system opeation can be descibed by the vecto diagam shown in Fig. whee i and u e ae the ms value of the fundamental hamonic Fouie expession. By neglecting R î in font of L ωî, we can wite: vˆ = û + jl î () e ω ɵv ɵu e î, ae complex epesentations of v, u e and i espectively. Usually, we seek to put the input fundamental cuent i in phase with the v voltage, the vecto diagam is then that of Figue -b. In this case, we can wite: U e V + ( LωI ) With: tg = () L ωi V δ = (3) δ: indicates the phase-shift of the input voltage fundamental u e with espect to the v voltage. Fo a pulse width modulation contol: - δ: is the phase-shift of the efeence being used to detemine the commutation times of the switches, egading to the supply voltage. The diection of phase-shift depends on the diection of the powe flow: - It is a lagging phase-shift if the souce povides powe to the load though the convete. - It is a leading phase-shift when the load etuns powe to the souce (invete). The fundamental value of the input voltage can be given by the elationship: Vc U e = (4) V c is the aveage value of the voltage v c. As is lowe than, V c is highe than U e Contay to the taditional ectifie which functions as depesso tansfomes, this convete functions as an elevato ectifie voltage [9]. The evesible opeation of the convete can be epesented by the following model: u i Fig.3 convete model This enables us to expess the elationships between the input values and those of the convete output that is: e s = K f = K i f v c k f : is the convete contol function, it depends on the switches K i closing and opening sequences: if (K ) close and (K 3 4 ) open if (K 4 ) close and (K 3 ) open (6) K f = o ( K 4 ) open and (K 3 ) close - if (K ) open and (K 3 4 ) close The cuent and the voltage equations at the convete input and output ae: di dt dv dt c v = i = s R i i C d L u e i d is the cuent absobed by the load, its equation depends on the natue of this one. - No load: i d = ; - Fo a esistive load R d : vc i d = Rd (8) - Fo a passive inductive load (L d, R d ): di dt v R i L d c d d = (9) d - Fo an active inductive load (L d, R d, E): did vc Rdid E = () dt L d (5) (7) Issue 4, Volume 5, 355

3 III. APPLICATION OF THE MODULATION STRATEGY In ode to study the convete pefomances in ectifying mode and its contol esponses, a digital simulation by applying a pulse width modulation technique is pefomed; it is about the tiangulo-sinusoidal stategy (S.P.W.M). III. TRIANGULO-SINUSOIDAL STRATEGY Pulse width modulation (PWM) techniques ae effective means to contol the output voltage fequency and magnitude. It has been the subject of intensive eseach duing the last few decades. Vaious PWM contol schemes have been discussed in liteatue. Basically they can be classified into two main categoies, one is caie based PWM and the othe is spacevecto PWM Especially, the space-vecto PWM is used fo thee-phase convete applications. Hee we mainly conside the caie based PWM appoaches that ae often applied to the single-phase applications []. Fig.4 above is a geneal scheme of PWM modulation. In ode to poduce a sinusoidal voltage at desied fequency, say ƒ, a sinusoidal contol signal Vcontol at the desied fequency () is compaed with a tiangula wavefom Vcaie as shown in (Figue 4), at each compae match point, a tansition in PWM wavefom is geneated as shown in (Figue4). When V is contol geate than V, the PWM output is positive and When V is caie c smalle than V, the PWM wavefom is negative. The caie fequency of tiangle wavefom V establishes the ectifie s caie switching fequency. We define the modulation index m as: () m i =.7, m ƒ =8, f=5hz, Veff=5V, C=45 µf, R = 5Ω, L =.H, R C = 8Ω, L C =.5H. The obtained simulation esults ae illustated by (figue 5). (Figue 5 a) shows the steady state cuent i which is in phase with the voltage v afte shifting the caie v p by an angle with espect to the voltage v. Refeing to the cuent i fom, it is clea that its fom is sinusoidal with a fom which follows the commutation switches sequences. (Figue 5 c) illustates the convete input voltage u e, (Figue 5 d) indicates the output convete cuent; we notice that it can take negative values in the case of the bipola ode; on the othe hand, it is always positive fo the unipola ode that justifies the ievesibility of this ode. (Figues 5-e and 5-f) show the voltage v c and the cuent load; it is seen that the voltage inceases to each a constant value. The inceasing time of the voltage depends on the used capacitance; it inceases with the inceasing of this one. The cuent load has pactically the same fom as v c voltage. Fig.4. Desciption of bipola PWM modulation Whee V contol is the peak amplitude of the contol signal, while V ti is the peak amplitude of the tiangle signal (caie). Also the fequency modulation atio is defined as: () m ƒ is the atio between the caie and contol fequency. Accoding to its definition, the tiangulo-sinusoidal command technique allows an adjustment by two paametes: - The modulation index m ƒ that influences the desied wave hamonic contents. - The atio of adjustment m i which influences diectly the effective value of u e. The compaison of the efeence sinusoidal signal with the tiangula wavefom is done in the PWM geneato of the DSP to geneate the contol signals fo the switching devices along with the inveted signals with the equied dead band. A 6-bit counte egiste is used to measue the fequency of the tiangula wave. A cented symmetic P W M signal is used which has maximum count up of 6 and count do wn 6. The P WM signals a n d the contol signals geneated ae given in (figue 4). By taking the following paametes: v otage v(v ) P W M v o lta ge u e (v ) c ue n t i(a ) time(s)(a) time(s)(b) time(s)(c) c u en t is (A ) v o lta g e v c (v ) load c uent id (A ) time(s)(d) time(s)(e) time(s)(f) Fig.5 bipola tiangulo-sinusoidal stategy III. BIPOLAR PWM SPECTRUM ANALYSIS Issue 4, Volume 5, 356

The total hamonic distotion (THD) fo this bipola PWM wavefom is about 84.97% as simulated by MATLAB. In (Figue 6), the esulted fundamental fequency component is.

4 The total hamonic distotion (THD) fo this bipola PWM wavefom is about 84.97% as simulated by MATLAB. In (Figue 6), the esulted fundamental fequency component is., which means the magnitude of desied output fequency equal to the value of DC input voltage Vd. The high fequency hamonics appeas at aound 45 th hamonics and again at aound 9 th hamonics. This indicates that fo bipola PWM, the high fequency hamonics will appea aound,, 3 and so on. To eliminate those high fequency hamonic intefeences, typical second-ode low-pass LC filtes can be used to filte them out. A powe cicuit fomed by two ams, fomed by fou tansistos I.G.B.T and fou diodes connected in anti-paallel. The geneated contol signals wee obtained using seveal contol cads such as conditioning, monitoing, D/A convesion cads. Fig.7 D.S.P. TMS3LF47 implementation diagam. Fig.6. Fequency spectum fo bipola PWM with m i =. and m ƒ =45 IV. EXPERIMENTAL TEST The schematic diagam of the convete cicuit implemented is given in (figue7). It has two pats, the contol cicuit and the powe cicuit. The shaded pat is the contol cicuit containing the DSP contolle TMS3LF47 that geneates the PWM signals and also povides soft stat function. Set point fo the modulation index and fequency is set by a compute though seial inteface. The low pass filte was designed in such way that the output voltage wavefom of the convete is sinusoidal. To stat with, the single-phase convete with the bipola switching scheme is simulated using simulink in Matlab and its pefomance is studied [], []. Late on, the single-phase convete was implemented using DSP TMS3LF47 and its pefomance was studied. A compaison is made of the esults obtained though simulation and expeimental wok unde the same opeating conditions. To veify the theoetical esults obtained on the AC/DC convete, we designed and built the vaious cicuits foming the full convete. Fig.7 Shows the D.S.P TMS3LF47 implementation diagam. The DSP pogamming was based on the softwae developed by Texas Instuments Code compose. The contol algoithm has been witten in assembly language in ode to optimize the whole tasks of opeation and communication between the DSP, the Convete and the Load [3], [4], [5], [6]. Afte the constuction of the vaious cicuits, the convete was tested in the laboatoy; it functioned as a ectifie supplying a passive load fomed by a esistance and an inductance. The oscillogaphic esults obtained ae given in (figues 9a, b, c, d, and e). Fo a tiangulo-sinusoidal stategy, a cyclic atio equal to.7 and the index of modulation equals wee taken. The effective value of the voltage deliveed by the auto-tansfome is 5V. The filteing capacitance at the out put of the convete is 45 µf. Fig.9-b clealy shows that the cuent i is in phase with the voltage v, theefoe the convete uns at unit powe-facto. The input voltage follows pefectly the imposed bipola contol. The v c voltage ises fom zeo to a final constant value, the ising time depends on the filteing elements used; it inceases when the placed capacitance C and inductance L take high values. The influence of the initial capacito chage was also checked. Issue 4, Volume 5, 357

5 a- The voltage v c b- the cuent i and the voltage v Fig.8 laboatoy bipola convete boad (Contol cicuit and powe cicuit) c- the voltage u e and the cuent i Issue 4, Volume 5, 358

6 d- the cuent i Fig. DSP contol output fo bipola at 5 Hz e- the cuent i and the voltage v Fig.9 some expeimental esults obtained by the application of the tiangulo-sinusoidal stategy. Fig.. fequency spectum of H-bidge output fo bipola at 5Hz V. CONCLUSION Issue 4, Volume 5, 359

A laboatoy model of a bipola single- phase convete was successfully implemented using DSP TMS3LF47 and tested. The ectifie unit consists of fou, discete I.G.B.

7 A laboatoy model of a bipola single- phase convete was successfully implemented using DSP TMS3LF47 and tested. The ectifie unit consists of fou, discete I.G.B.Ts connected as a bidge and dive with a low cost dive. The expeimental esult matched with simulation esults. Although any paametes ae adjusted fo giving fundamental fequency. Thus AC/DC single-phase convete was studied and built. This convete allows an opeation at a unit powe-facto by intoducing a phase-shift of the caie signal with espect to the supply voltage fo the tiangulo-sinusoidal stategy. The esults obtained by simulation o expeimentally ae vey close. They show that: - The amplitudes of the convete input and output values depend on the cyclic atio fo the tiangulo-sinusoidal stategy. - The wavefom values ae affected by the modulation index fo the tiangulo-sinusoidal stategy. - The functional evesibility of the convete is assued. [9]. Seguie G., Labique F.: Les convetisseus de l électonique de puissance. Tome IV la convesion continu altenatif (Powe Electonic Convete. Tome 4: diect-altenative convesion). Edition : TEC & DOC, Lavoisie, 89 pp []. Yip S.C., Qiu D.Y., Chung H.S., Hui S.Y.R.: A Novel Voltage Sensoless Contol Technique fo a Bidiectional AC/DC Convete. IEEE Tans. Powe electonics, Vol.8, No. 6, Novembe 3. []. Texas instuments: Implementation of a Speed Field Oiented Contol of 3- phase PMSM Moto using TMS3F4. Application Repot SPRA588. []. Ben Hamed M., Sbita L. and Abboud W. '' Neual Netwoks fo contolled Speed Sensoless Diect Field Oiented Induction Moto Dives'', JEE, Vol. 8, No., 8. [3]. Yang Mei, Daning Zhou, Lipei Huang and Kouki Matsuse, Application of matix convete in auxiliay dive fo diesel locomotives, IAS 5. [4]. Ezoji H., Sheikholeslami A., Tabasi M. and Saeednia M.M. Simulation of Dynamic Voltage Restoe Using Hysteesis Voltage Contol Euopean Jounal of Scientific Reseach ISSN 45-6X Vol.7 No. pp.5-66,9. [5]. Alph M.ennel. Linke M., Szczupak P., Sensoless Contol of 4- Quadant-Rectifies Voltage Souce invetes (VSI). Wuppetal- Gemany, 3 IEEE. [6]. Malinowski Maiusz., Jasinski Maek., Maian P.azmiekowski. Simple Diect Powe Contol of Thee- Phase PWM Rectifie Using Space- Vecto Modulation (DPC- SVM). IEEE Tans. ind. Electonics, VOL. 5, N., APRIL 4. REFERENCES []. Dixon J. W.ulkani A. B., Nishimoto M.: Chaacteistics of a contolled-cuent PWM ectifie-invete link. IEEE Tans. Indus. Appl, Vol. IA-3, No.6, Nov./Dec.9 88, pp. -8. []. Stihi O., Ooi B. T.: A single phase contolled-cuent PWM ectifie. IEEE Tans. Powe Elect. Vol. 3, No.4, Oct 988, pp [3]. Wiechmann E. P., Ziogas P. D., Stefanivic V. R.: A novel bilateal powe convesion scheme fo vaiable fequency static powe supplies. IEEE tans. Indus. Appl, Vol. IA-, No. 5, Septembe /Octobe 985, pp [4]. Ooi B.T., Salmon J.C., Dixon J.W.ulkani A. B.: A thee phase contolled cuent PWM convete with leading powe facto.ieee Tans. Indus. Appl. Vol.IA-3, No:, Januay/Febuay 987, pp [5] H.Denoun, M.Zaouia, M.Rachek. study and ealisation of thee-level IGBT voltage souce PWM invete to feed a synchonous machine, WSEAS tansactions on cicuits, Issue 6, vol 4, june 5, ISSN 9-734, pp [6] M.Rachek, M. Zaouia, H.Denoun. Two-dimentional Finite Element Modelling of Eddy Cuent Non Destuctive Testing fo Defect Simulation and Detection and Senso Movement Simulating by Geometical Band technique ISSUE 6, VOL 4, June 5, ISSN 9-734, PP [7] K.H.Edelmose. Gid Coupled Thee Level DC-to-AC powe Invete ISSUE 6, VOL 4, June 5, ISSN 9-734, PP [8] H.Denoun, M.Zaouia, M.Rachek. study and ealisation of thee-level IGBT voltage souce PWM invete to feed a synchonous machine, poceeding of the 9 th Intenational confeence on cicuits and systems, Geece, 5. Authos infomation Dépatement d Electotechnique, Faculté de Génie Electique et d Infomatique Univesité Mouloud Mammei de Tizi-Ouzou, B.P 7 R.P Tizi- Ouzou 5, Algeia, (akim_danoundz@yahoo.f) Dépatement d Electotechnique, Faculté de Génie Electique et d Infomatique Univesité Mouloud Mammei de Tizi-Ouzou, B.P 7 R.P Tizi- Ouzou 5, Algeia, (benamouchen@yahoo.com) 3 Dépatement d Electotechnique, Faculté de Génie Electique et d Infomatique Univesité Mouloud Mammei de Tizi-Ouzou, B.P 7 R.P Tizi- Ouzou 5, Algeia, (hddsalah@yahoo.f) H. Denoun was bon in Algies, Algeia. He eceived the degee in electical engineeing fom the Mouloud Mammei Univesity, Tizi-Ouzou, Algeia, and the D.E.A degee fom Pais6, and the Magiste degee fom Polytechnic School, Algies, Algeia in 998 and espectively. Pesently he pepaes the PhD degee in the Mouloud Mammei Univesity, Tizi- Ouzou, Algeia and he is Assistant-Pofesso. His eseach inteests include electical machines and dives, powe electonics and contol systems. N. Benamouche eceived his PhD in Electical Engineeing fom The Univesity of Sheffield, U.K. He woked as teaching assistant at the Univesity of Leeds in 99/99, and as a Head of Depatment in Najan Technical Issue 4, Volume 5, 36

8 College of Technology, Saudi Aabia, fom -4. He is cuently a pofesso at the Electical Engineeing Depatment, Univesity of Tizi-Ouzou, Algeia, and occupies the chai of Vice Chancello to postgaduate studies and eseach at the same Univesity. His eseach inteests include electical machines and dives, powe electonics and contol systems. S. Haddad eceived his Enginee, DEA and PHD degees in Electical Engineeing in Algeia and Fance in 985, 986, and 99 espectively. He is cuently a pofesso at the Electical Engineeing Depatment, Univesity of Tizi-Ouzou, Algeia, His eseach inteests include electical machines and dives, powe electonics and contol systems. Issue 4, Volume 5, 36

An Efficient Control Approach for DC-DC Buck-Boost Converter

An Efficient Control Approach for DC-DC Buck-Boost Converter 2016 Published in 4th Intenational Symposium on Innovative Technologies in Engineeing and Science 3-5 Novembe 2016 (ISITES2016 Alanya/Antalya - Tukey) An Efficient Contol Appoach fo DC-DC Buck-Boost Convete